So maybe my title is a little extreme, but sometimes there are valid reasons you need to record a phone conversation — interviews for podcasts and research are the two I get asked about the most. Just keep in mind that recording telephone calls requires the consent of the parties involved, and it’s good practice to record as part of the interview the subject expressing their willingness to have the call recorded.
There are 3 kinds of phone systems: analog, digital & VoIP. On campus currently we have a combination of analog and digital. The digital version will likely fry any recording device designed for analog phone systems so it’ll be important for you to know what type of line you have before you plug anything in.
There are a couple of different devices that us a standard microphone jack connected to a recording device to capture telephone conversations.
The first is a traditional in-line recording coupler. You plug one line into the wall jack, then plug the phone into this device. It has a separate line out to your microphone jack. Most of these only work with normal phone jacks, and if you’re using VoIP it may be incompatible.
The second is an ear piece you place in the ear you’re using to listen, and it picks up both sides of the conversation.
Of course, if you’re a Google follower, you may realize that you can record any incoming calls to your Google Voice number by pressing the “4″ key on your phone. Both parties receive a confirmation that the call is being recorded and when you hang up (or press “4″ again) it saves the recording to your account. There is a history tab where you can listen within the app or download a mp3 of the conversation to your computer.